The use of plastics has become pervasive in present-day products of all types. The processes by which plastics are formed into or integrated as specific elements with the products have been carefully developed to generally maximize the volume of product output and performance characteristics of the resulting plastic products. Typically, the polymer process is used to form an individual product or element, such as a packaging structure (plastic bottle) or an individual element of a larger article (gear member for a low power drive train, or a filament of thermoplastic for combining into yarn or synthetic textiles).
The traditional and well-known plastic forming processes include, among others, injection molding, blow molding, and extrusion. Each of these forming processes has several related sub-processing techniques, but in the end they all rely on at least one common characteristic: the plastic starting material must be transformed into a molten state for the process to perform as desired. The molten thermoplastic stream is generated by masticating plastic pellets (and perhaps some “regrind” from the offal of previous molding processes) to work heat the resulting mass to molten temperatures. This molten requirement mandates the use of relatively complex equipment, and the processing parameters must be precisely controlled for successful processing. These forming processes are also somewhat limited in that there are limitations on the type of products that can be made. The material parameters of the final products made using these forming processes, such as surface properties, chemical resistance, electrical properties, optical properties, melt properties, tensile strength, shear strength, elasticity and rigidity can be compromised as a result of these traditional plastic forming processes. Some of these forming processes also create substantial scrap material that may be later recycled into the molten plastic prior to continued processing.
These limitations become more important when the desired product made of the plastic is required to be flexible, durable, strong and easily assembled, such as a non-textile fabric. Non-textile fabric here means a generally flexible web made of individual interconnected elements, the web having many of the characteristics of textile fabric, but not depending on fibers or fiber related processes for these characteristics. Chain mail is one example of a non-textile fabric.
Another plastic forming process is solid phase forming, also called superplastic forming by Shell Development Company, and “Scrapless Forming of Plastic Articles” by Dow Chemical Company. This solid phase forming process is used to create plastic articles having high heat distortion temperatures, expanded or porous layers with integrally formed skin, using ultra high molecular weight polymers, and blended or layered structures of two or more materials. A related process is also used in the forming of metals, particularly aluminum, to form forged aluminum shapes from precisely formed slugs of metal. While solid phase forming can be used to create plastic products that generally overcome the short falls of the previously described forming processes, solid phase forming itself has not been utilized to directly form an interconnected structure.
Another shortcoming of these plastic forming processes is that the subsequent manufacturing steps for integrating the formed product into the final embodiment includes further handling of the formed product. This further handling to assemble the final product is expensive, both in labor costs and speed of production.